X80 pipeline steel used for longitudinal resistance welded pipe and method for producing its hot rolled coil

The invention provides an X80 pipeline steel used for a longitudinal resistance welded pipe and a method for producing a hot rolled coil of the X80 pipeline steel used for the longitudinal resistance welded pipe. The X80 pipeline steel used for longitudinal resistance welded pipe comprises the following components: 0.025%-0.065% of C, 0.10%-0.35% of Si, 1.68%-1.85% of Mn, 0.06%-0.11% of Nb, 0.20%-0.35% of Cr, Ni <=0.25%, Cu<=0.25%, V<=0.04%, 0.005%-0.020% of Ti, 0.015%-0.045% of Als, 0.001%-0.004% of Ca, N<=0.006% and the balance of Fe. The preparation method comprises the following steps of pretreating molten iron, smelting in a converter, externally refining, continuously casting and rolling, directly heating continuous casting billet in a heat charging at the temperature of 500-850 DEG C, heating to the temperature of 1130-1230 DEG C by a stepping type heating furnace, controlling the rolling through two phases of rough rolling and finishing mill set, wherein the blooming temperature is 1100-980 DEG C, the finish rolling temperature is 960-750 DEG C, and the finishing rolling temperature is 750-830 DEG C, rapidly cooling a steel coil through laminar flow cooling with speed of 10-20 DEG C/s, wherein the reeling temperature is 480-560 DEG C. The invention has the advantages of low alloy cost, short production period, high efficiency and saved energy, the product has good comprehensive strength and toughness performance as well as welding performance.